The present invention relates to a construction element, a method of making a construction element and a tool for making a construction element. More particularly this invention concerns such a construction element formed by a pair of metallic profiles extending longitudinally parallel to each other and joined by a longitudinally extending bar of insulating material.
A construction element is known comprising a pair of metallic profiles extending longitudinally parallel to each other and joined together by means of a longitudinally extending bar of insulating material. Thus, for instance, each of the profiles is formed on its side turned toward the other profile with a pair of groove-defining flanges. One edge or side of the insulating bar is held in the groove of one of the profiles and the other side or edge of the insulating bar is held in the groove defined by the flanges of the other profile. In this manner the two metallic profiles, by which is meant elongated unitary metallic elements of profiled cross-sectional shape, are joined together without touching each other so that the two are relatively insulated with respect to heat and electricity. Nonetheless, the construction element formed by such a three-part assembly is quite rigid. It is known to use this type of construction element as a door or window molding between locations of different temperatures so that minimum heat transfer take place. Such an arrangement is also used in refrigeration devices and the like.
Typically the flanges forming the grooves that receive the sides of the insulating bar are inclined slightly toward each other and the sides of the insulating bar are given a dovetail cross-sectional shape. In order to assemble such a construction element the edges of the insulating bar are merely slipped longitudinally into the correspondingly trapezoidal-shaped grooves in the profiles.
The considerable disadvantage of this type of construction element is that when assembled the various parts, although transversely locked securely together, can often slip longitudinally relative to each other. Furthermore the parts often fit somewhat loosely so that the construction element is not usable for a watertight joint. What is more the assembly of such an arrangement is frequently bothersome, in particular when a particularly long construction element must be employed, as the longitudinal slipping-together of the various parts requires considerable floor space and precision.